Anti-fingerprint surfaces — a trend that’s here to stay

This paper explores the development of 'Slim Skins,' a novel glazed façade system designed to address the increasing demand for highly transparent buildings while simultaneously reducing environmental impact through efficient resource utilization and lower embodied carbon. Drawing inspiration from Mies van der Rohe's "skin and bones" concept, the research tackles the challenge of achieving maximum transparency in modern building design without compromising energy efficiency or structural integrity. The article highlights that traditional curtain wall systems, despite their popularity, often fall short of desired transparency due to their protruding frames (mullions and transoms). Structural glass systems offer high transparency but are often inefficient in material use, time-consuming to design, and costly, leading to higher environmental footprints. The 'Slim Skins' system proposes a solution by integrating the frame within the glazed units, making the glass work structurally. This approach, building on previous research, particularly Cordero (2015), utilizes composite action where the frame is adhesively bonded between the glass panes. This not only allows for a lower thermal transmittance but also creates a significantly slimmer façade element. The paper details the methodology, which began with a literature review and the establishment of design scope and requirements based on Dutch building codes and industry standards. Various design iterations, including different profile shapes for the integrated mullions, were assessed for structural feasibility using finite element models (FEMs) and hand calculations, focusing on stiffness and strength requirements like deflection and stress. The study found that profiles with greater contact surfaces between the mullion and glass achieved higher composite action, leading to improved structural efficiency. A key aspect of the research is the sustainability assessment, which evaluates the end-of-life environmental impact of the 'Slim Skins' system compared to existing façade systems, such as the Triodos Bank project. The assessment, following the method developed by Hartwell & Overend (2019), analyzes different end-of-life scenarios: landfill, recycling (including downcycling and energy recovery), reuse of components, and full system reuse. The study demonstrates that reuse scenarios (component reuse and full system reuse) offer significantly greater environmental savings in terms of embodied energy (EE) and global warming potential (GWP) compared to recycling or landfill. Notably, full system reuse, particularly for unitized systems like 'Slim Skins,' provides the highest environmental benefits by avoiding material separation and enabling easier relocation. While structural assessments required adjustments, such as increasing glass thickness for certain profiles to meet deflection and stress requirements, the 'Slim Skins' system aims to combine the high transparency of one-way spanning glazing with the economic efficiency of unitized curtain wall systems. The final design, which incorporates glass fibre reinforced polymer (GFRP) profiles attached to glass panels, achieves flush construction with minimal visible opaque materials. The system is designed for factory assembly, allowing for efficient production and on-site installation by attaching panels to slab edges. Challenges include the intricate profile design requiring high precision during construction and the extensive use of adhesive, which can complicate disassembly for recycling but facilitates full system reuse. The research concludes that the 'Slim Skins' system offers a viable, transparent, and more sustainable alternative for modern glazed façades by leveraging composite action and prioritizing reuse in its end-of-life strategy. #SlimSkins #GlazedFaçade #SustainableArchitecture #CompositeAction #GlassDesign #BuildingTechnology #EmbodiedCarbon #UnitizedSystems #EnvironmentalImpact

The era of ubiquitous computing has seen significant advancements in visual displays, yet haptic feedback technology remains in its early stages. This paper introduces the concept of active electronic skin (AE-Skin) as a solution to bridge this gap, enabling ambient haptic feedback on various physical surfaces. The AE-Skin is characterized by three key features: richness, interactivity, and invisibility. Richness refers to the ability to provide multi-modal haptic stimuli, including texture, thermal, and vibrotactile feedback, alongside multidimensional tactile sensing. Interactivity emphasizes bi-directional sensing and actuation capabilities, allowing the skin to perceive user interactions and dynamically adjust its output. Invisibility highlights its transparent, ultra-thin, flexible, and stretchable properties, ensuring seamless integration into daily objects without obstructing functionality or appearance. The potential applications of AE-Skin are categorized into two main areas: the physical world and the digital world. In the physical world, AE-Skin can be integrated into intelligent homes (e.g., smart wallpaper displaying various textures, smart tablecloths adjusting temperature), intelligent cars (e.g., steering wheels monitoring physiological parameters and providing warnings, car panels with haptic buttons for intuitive control), and intelligent museums (e.g., dynamic exhibits simulating textures and temperatures of artifacts). For the digital world, AE-Skin can enhance haptic screens (e.g., rendering fabric sensations for online shopping, providing tactile guidance on in-car displays), wearable VR devices (e.g., simulating tactile and thermal sensations in virtual environments via gloves or vests), and bare-hand VR devices (e.g., offering multi-modal tactile stimuli for virtual objects). The article further delves into the key technologies underpinning AE-Skin, including texture display, temperature rendering, vibration rendering, multidimensional tactile sensing, and materials/fabrication methods. Texture display technologies are discussed based on electro-active materials, electromagnetic actuation, shape memory alloys/polymers, pneumatic actuation, and other methods like liquid crystal elastomers and artificial muscles. Temperature rendering devices primarily utilize Peltier elements and thermo-resistive heaters, with considerations for flexibility, response speed, and safety. Vibration rendering techniques often employ electromagnetic-based motors and pneumatic actuators, highlighting the importance of comfort and wearability. Tactile sensors are explored based on their transduction mechanisms (piezoresistive, capacitive, piezoelectric, electromagnetic, optical, and triboelectric) and their ability to detect various interactive signals such as pressure, strain, and temperature. The discussion also covers advanced materials like polymers, smart materials (electroactive, magnetically responsive, phase change), and nanomaterials, alongside fabrication methods like soft lithography, molding, and 3D printing. Finally, the paper identifies research gaps and outlines future directions to realize ambient haptic interaction. These include deepening the understanding of human skin's physiological and perceptual mechanisms (biomechanical models, perception thresholds, haptic illusions), addressing spatial-temporal registration among multimodal haptic stimuli (structural design, mode alignment, power supply), improving integration between sensing and actuating units (spatial layout, compatibility, large-scale control), and enhancing spatial-temporal registration between visual and haptic displays (transparency, thickness, stretchability, virtual-real alignment). The long-term goals involve developing advanced functional materials and seamless visual-tactile integration to create a truly ambient haptic world. #ActiveElectronicSkin #AmbientHaptics #HapticFeedback #UbiquitousComputing #HumanComputerInteraction #MultimodalSensing #TactileDisplay #WearableTechnology #SmartSurfaces